Due in greatest part to the ever increasing concern for our environment, the problems associated with the disposal of refuse vehicle tires has received much attention in the recent years. Burial of refuse tires has proven to be an unsatisfactory disposal alternative. Thus, with an increasing frequency they have been stored in dumps, wherein they present a constant fire hazard and otherwise, a convenient breeding ground for mosquitos and other non-beneficial insects that flourish within pocket of water trapped in them.
Although it is recognized that refuse tires can be burned for the generation of power, cost efficiency and environmental considerations have made this alternative unfeasible in most instances.
Re-capping of old tires has proven to be unfeasible since the longer molecules which impart strength to the rubber are broken down during the remolding process.
Recycling would appear to be the only reasonable alternative to deal with the growing problem. There are, however, many problems that effect the cost efficiency of various recycle schemes which have been proposed in prior years. Modern tires are of a composite construction which can include bead wires or wire mesh, and steel or fiber belting, in addition to the profitably recoverable rubber component. Hence, energy and equipment intensive solids separation processes have been used in the past to recover the rubber. Exemplary of such schemes are U.S. Pat. Nos. 3,721,392 and 3,658,267 to Burwell, which both show removal of rubber from refuse tires by abrasion with an endless belt or sander.
U.S. Pat. Nos. 3,693,894 to Willette and 1,498,935 to Shull disclose cutting members as an alternative to the abrasive members of Burwell.
U.S. Pat. No. 5,322,792 to Peguy, teaches the shredding of worn tires by high speed grinder chains, while U.S. Pat. No. 4,840,316 to Barclay, discloses a high speed, rotating rasp.
All of the foregoing machines employ high speed components, which have the common disadvantages of higher energy consumption, heat buildups more rapid apparatus component wear and longer down-time.
On the other hand, the instant invention avoids the disadvantages of the prior art, by providing an apparatus and method which treats pre-softened portions of refuse tires, thereby enabling the denuding of the rubber component from the metal or fiber component of the portions, by slow speed compaction grinding.
Therefore, It is an object of the instant invention to provide an apparatus and method which recover rubber crumb from refuse tires with a reduced energy requirement.
It is a further object of the invention to provide an apparatus and method which recover rubber crumb from refuse tires with minimal wear to apparatus components.
It is a further object to provide a method and apparatus of simple and more reliable design which provides reduced down-time and increased cost efficiency.